<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <!-- 2 出现的次数 -->
    <script>
      var timece = function (n) {
        let arr = []
        for (let i = 0; i <= n; i++) {
          arr.push(i)
        }
        return arr
          .join('')
          .split('')
          .filter(item => item == 2).length
      }
      console.log(timece(25))
    </script>
  </body>
</html>
